Calf muscle oxygen extraction fraction measurement using the multi contrast EPI with keyhole sequence – feasibility study.

Motivation: Muscle Oxygen extraction fraction (OEF) may provide a potential biomarker of muscular disease. Goal(s): The aim was to investigate application of a recently developed multi contrast EPI with keyhole sequence (GE-SE-EPIK) to quantify OEF in skeletal muscle. Approach: Sequence was used to measure T2, T2* and OEF in healthy volunteers calf muscle at rest (to test reproducibility) and during a cuff compression (to test sensitivity to detect dynamic OEF changes). Results: Values of T2, T2* and OEF measured at rest, correspond to those in literature. Sufficient reproducibility and sensitivity suggest suitability of GE-SE_EPIK for in vivo measurements for functional imaging of calf muscle. Impact: This work supports the feasibility of using a recently developed multi contrast EPI with keyhole sequence to quantify T2, T2* and oxygen extraction fraction in skeletal muscle. This could prove a valuable tool for studying oxygen metabolism in muscles in health and disease.